Saw sharpening machine



1943. J. 1. UNDERWOOD SAW SHARPENING MACHINE 5 Sheets-Sheet 1 Filed Sept 4, 1942 Jkrz I Vzderwaoafi Nov. 9, 1943;

- J. I. UNDERWOOD SAW SHARPENING MACHINE Filed Sept. 4, 1942 5 Sheets-Sheet 2 NH IHH Jmfyzderwvod y I I and WWW; Em

Nov. 9, 1943. I J. UNDERWOOD 2,334,136

SAW SHARPENING MACHINE Filed Sept. 4, 1942 5 Sheets-Sheet s I Q i w i l \1 \f m If; m U N 8 Q Q N f \x I p l..- V o l m m I l l N 1 \Q N x l I w i 22 53 m I? N l I l I m 3 l a I I 1 c I 5 l I l \BLPJ Inventor fizwjymderwmd WWW Nov. 9, 1943.

J. l. UNDERWOOD SAW SHARPENING MACHINE Filed Sept. 4, 1942 5 Sheets-Sheet 4 By @Mfldiw.

WWI we; 16m

Nov. 9,1943.

5 Sheets-Sheet s Filed Sept. 4, 1942 C,6.JT

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m w W W W 4 U N M Patented Nov. 9, 1943 w see iwmrpme ful improvements in saw Sharpeners designed primarily for use in sharpening the saw of a double end trimmer, or for similar trimming saws used in conjunctionwith planing mills.

An important objectof the present invention ed for mounting in position on the machine and embodying means for feeding the 'teethof the, saw in a step by step'movem'ent for engagement by the abrasive wheel of the sharpener, together with means for raising and lowering the-abrasive wheel into its position for sharpening the-successive teeth of the saw and also embodying means forchanging the angle of 'the abrasive'wheel for sharpening the bevel on opposite sides of the is to provide a saw sharpening apparatus adaptteethof the saw; and to further'provide a m af chine of this character adapted forsharpening the saw withoutthe necessity of removingfthe saw from the saw machine.

A still further object is to provide an appjara I tus of this character of simpleand practical construction, which is efficient and reliable .in performance, relatively inexpensive to manufacture and maintain in operation andotherwise well adapted for the purposes for which the same is intended. I 7

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed; reference being had tothe accompanying'drawings" forming part hereof,

parts throughout and in which:

- Figurel is atop plan view. i Figure 2 isa front elevational View. Figure 3 is arear elevational view. Figure is a side elevationalview. i

.F'igure 5 is an enlargedxfragmentary detail of the oscillating mechanismifor. moving/the abrasive wheel into its opposite angular positions. Figure 6 isa detailcf the-cam actuated rock shaft for feeding the saw in a step by step movement. Figure '7 is a detail of the cam actuated mechanism for raising and lowering the abrasive Wheel.

wherein like numerals refer 'to like I .from and by means of whichthe bearing support t 511 with the abrasive wheel, 36 th e upper end of an upstanding rod 35 rising from one endof a bar 36 pivoted intermediate its ends as at 31 on the platform for-horizontal oscillating movement. Totheother end of the bar 36 is pivotally secured a sectionallink 38 composed of 1 telescoping sections 39 and i 40, one. end: of: they Referring now to the drawings in detaihwh ere I V in for the purpose of illustrationl have disclosed v a preferred embodiment of the invention, the numeral 5 designates a platform having spaced parallel beams "5 at th e opposite sides thereof adapted to rest on the frame of a double end j trimmer or' similar saw machine (not shown); K the beams having a notch-l in the underside thereof to accommodate the shaft 8 to which the saw 9- is secured. The ends of the beams '6 project outwardly from the front andrear edges-of the platform to provide hand grips ill to facilitate the placing of the saw'sharpening apparatus into and out of position with The platform 5 is formed with a slot H through which the saw respect to the saw machine,

9 projects.

A shaft 12 is journaled adjacent oppositeends ,in bearing supports l3-l;3rising from the plat form, the shaft, being driven by a belt M and pulleys l5 and I6 secured respectively to the shaft and to a motor I1 mounted on the platform.

A frame is is Also secured to the free end of the. frame 18 is 1a Li -shaped bracket 26 having a bearingsupport 27 vertically disposed therein and mounted for.

- pivotal movement in the bracket 26. To the lower endof the support 21 is secured a bear ing 28 in whichz shaft 29 is. journaled, the shaft.

.29 havinganabrasive wheel 30 securedat one end and is provided with a pulley-3i at its opposite end driven by a belt .32 from the pulley 23.;

To the upper'end of the bearing support 21 is secured a handle 33projecting horizontallytheremanually oscillated.

Projectin downwardly from the bearing sup-' port 21 is a yoke 3 in'which is positioned the section lil being pivoted to a balland socket connection M on the platform. The section 39 is 1 fornie'dwith a'shoulder 4-2 "and the section 4|] is formed with a shoulder 43 between whicha coil spring 44 is positioned undertension-to maintain thebar 35 in either of its off-centerpositions with respect'to the bar 36 as indicatedbythe fun and dotted line positions in Figure l of the drawings.

To the end of the bar 3's oppositefronithelink j "38 is a laterally' extending arm pivotally at-w pivotally supported at one end onythe shaft l2, the'opposite end of theframehavingabearing support 19 rising therefrom on the upper endof which a bearing 20 is supported having a shaft 2| journaled therein, each end of'the shafthaving pulleys 22' and 23 secured thereto; The pulley 22 is driven by a :belt 24 f from a pulley 25a1so secured to the; shaft l2.

may be I bracketslZon the platform. a 1 The shaft 'H has'arcollar 13 secured thereto provided'with a radially extending lug 14 through which an adjusting screw 15 is threaded and rse-- tached at its outer end to a curved member 46 which is pivoted intermediate its ends as at 41 on a support 48 of the platform. The ends of the member 46 are provided with rollers 49 engageable by a cam 50 for rocking the member 46 in opposite directions during rotation of the cam.

The cam 50 is secured on a shaft 5| journaled in bearing brackets 52 supported on the platform, one end of the shaft 5| having a worm gear 53 secured th'ereto driven by a worm 54 on the shaft l2.

Also secured on the shaft 5| i an elliptical cam 55 riding under a roller 56 iournaled at one. end of an arm 51 which is pivoted at its opposite t, endas at 58 on the platform. A coil spring 59- positioned under the arm 5?, adjacent its pivoted end, urges the arm upwardly to counterbalance the weight of the arm and the mech attached thereto. g

A yoke 60 is pivotally mounted on a pin 6| intermediate the ends of the arm 5'l, the'yo-ke hav 1 ing a block 62 pivotally supported thereon by the trunnions 63 and threaded through the block is a screw '64 whichis also threaded through a pivotallymounted block fi5'carried at'an intermediate portion of the frame IS. The upper-end of the screw is formed with a manipulating hand wheel 66.

Accordingly, through the operation of the cam 55; and arm 51 the screw 64 and frame ware raised and lowered whereby to raise and lower theabrasive wheel 30 into and out of engage ment withthe teeth 9" of the saw 9. The throw of the frame l8 in its upward and downward movement is regulated by the adjustment of the screw 64in a manneres will. be apparent while at the same time the abrasive wheel 30is oscillated to change the angle thereof so as to sharpenthe'beveling on the opposite teeth of the. saw

, by'means of the cam 50,.the curved member 46', arm 45 and upstanding pin 35 which engages the ivotalsupport 27 of the abrasive .wheel through the yo'ke34. 2

Th'esaw 9. is moved in a step by step movement for successively sharpening the teeth/of the'sawby means of a.pin-Bldispose'dtransversely f the saw for engaging the't'eeth there of, the'pin being mounted on the outer end of an arm 68 pivoted as 'at'69 on the upper end; of'

a lever -.10 secured on a shaft?! 'journaled in cured in adjusted position by a wingrnut 16. ,One end of the screw 15 engages an .extension 'llon oneend of an. arm 18 freely mounted onthe' shaft H; the other end of the arm 18', having a roller 19.journaled thereon positioned under and engaged by. aidouble-endeclcam so also secured on the 'shaft 5|. The ,cam 80 actuates the shaft H through the arm 18; extension ll, lug 14 and collar 13-, the cam 80 rocking the; shaft H in'one directionwhile the spring-ti. attached to theupper end of the lever actuates the shaft H and platform acts as. an ad ustable stop with which anism an intermediate part of the frame [8 engages to:

limit its downward movement.

From the foregoing it will be apparent the raising and lowering movement of the frame I8 5 will raise and lower the abrasive wheel 30 into and out of engagement with the teeth of the saw, as the latter is moved by the arm 68.

The angle of the wheel 30 is changed to prop-" erly grind the leveling on the alternately ar- 10 ranged teeth ofthe saw by the oscillation of the support 21;:

It is believed the details of construction, ad-' be readily understood from the foregoing without furtherdetailed explanation.

Having .described the claimed asnew is:

' '1. A saw sharpener comprising in combination amechanism for moving the saw in a step by step movement, an abrasive element, means for raising and lowering the abrasive element into and out of sharpening engagement with successive teeth of the saw, and means for oscillating the. axis ofthe abrasive element to move cthe latter into different angular positions with respect to the angularity of the teeth, said last named means comprising a pivotal mounting" for the abrasive element, a yoke carried-by the mounting, .a. pivoted bar having a member at golfone end engaging the yoke, mechanism con,

nected tothefbar for operating the'latter in opposite directions, and spring means engaging the bar to yieldably maintain the bar in its oppo- 1 site positions. s I, F

engaging the wheel with the teeth of asaw. and means operatively engaged by another of said camsyfor oscillating the axisof the wheel into differentwangular positions in accordance.

with the angularityof the teeth.

.3. A saw sharpener comprising an abrasive wheel supportmounted for vertical pivotalmove,

ment, an abrasive wheel rotatably; andoscillatably mounted on the support, a cam shaft, cams. ion the shaft, a pivoted arm extending trans-,

versely of thesupport and actuated by one ofthe cams, an adjusting screw connecting the arm:to1 the support for moving the support -for-engag-.; ing the wheel with the teeth of a saw. means op- ...eratively engaged by. another of said cams for oscillating the axis of the wheel lintodiiferent angular positions inv accordance with the angularity of the teeth, and means v for continuously and for operating the cam shaft. 4. A portable saw sharpener comprising a plat form adapted-for removably mounting "on a saw machine and having a slotted opening for re? ceiving a saw to be sharpened, a cam shaft step by step movement, an abrasive wheel rotat- 7 ably, oscillatably and pivotally mounted on the .i platform for bodily moverent into and out of,

engagement with the saw, a pivotal mounting for the axis of the wheel for changing the angle of the wheel with respect tothe-teeth of the saw,

vantages and manner of use of the device will invention, what is '2. A saw sharpenercomprising apivoted abrasive wheel support, an abrasive wheel rotatably and oscillatably. mounted on the support, a .cam, shaft, camson the1shaft; a pivoted arm connected transversely to the support and actuated fby one of the cams for moving the-support for" 1 rotating the 'wheelduring its bodily movement"v "mounted on the platform, cams on the shaft I mechanism on the platform operated by one of the cams forengaging and moving the saw a and mechanism onthe;;platformrespectively optatably, oscillatably and pivotally mounted on,

the platform for bodily movement into and out of engagement with the saw, a pivotal mounting for the axis of the wheel for changing the angle of the wheel with respect to the teeth of the saw, mechanism on the platform respectively operated by the remaining cams for oscillating and .pivotally actuating the wheel and a power means on the platform for operating the shaft and for rotating'the abrasive wheel.

JOHN I. UNDERWOOD. 

